#include <bits/stdc++.h>
using namespace std;
#define task "task"
#define fi first
#define se second
#define pb push_back
#define FOR(i, a, b) for(int i = (a), _b = (b); i <= _b; i ++)
#define FORD(i, a, b) for(int i = (a), _b = (b); i >= _b; i --)
#define bit(x, i) ((x >> i) & 1)
#define oo 1e18
#define all(v) v.begin(), v.end()
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
// mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
// ll rand(ll l, ll r) { assert(l <= r); return uniform_int_distribution<ll>(l, r)(rd); }
const int N = 1e5 + 5;
const int mod = 1e9 + 7;
const int base = 31;
int n, k, sz[N], bit[N], mark[N], sus = 0;
ll ans = 0;
vector<pii> g[N];
bool del[N];
void init(void){
cin>>n>>k;
FOR(i, 1, n - 1){
int u, v, w; cin>>u>>v>>w;
g[u].pb({v, w});
g[v].pb({u, w});
}
}
int dfs_sz(int u, int p){
sz[u] = 1;
for(auto [v, w] : g[u]) if(v != p && !del[v]){
sz[u] += dfs_sz(v, u);
}
return sz[u];
}
int findCentroid(int u, int p, int child){
for(auto [v, w] : g[u]) if(v != p && !del[v] && sz[v] > child / 2)
return findCentroid(v, u, child);
return u;
}
vector<pii> val;
void dfs(int u, int p, int d, int W){
val.pb({W, d});
for(auto [v, w] : g[u]) if(v != p && !del[v])
dfs(v, u, d + 1, max(W, w));
}
void update(int i, int val){
for(i; i < N; i += i&-i){
if(mark[i] != sus){
mark[i] = sus;
bit[i] = 0;
}
bit[i] += val;
}
}
int get(int i){
int ans = 0;
for(i; i > 0; i -= i&-i){
if(mark[i] != sus){
mark[i] = sus;
bit[i] = 0;
}
ans += bit[i];
}
return ans;
}
void calc(int u){
sus ++;
int child = dfs_sz(u, 0);
int c = findCentroid(u, 0, child);
val.clear();
val.pb({-1e9, 0});
for(auto [v, w] : g[c]) if(!del[v])
dfs(v, c, 1, w);
sort(val.begin(), val.end());
for(auto [w, d] : val){
if(w - d - k >= 0) ans += get(w - d - k + 1);
update(d + 1, 1);
}
for(auto [v, w] : g[c]) if(!del[v]){
val.clear();
dfs(v, c, 1, w);
sort(val.begin(), val.end());
sus ++;
for(auto [w, d] : val){
if(w - d - k > 0) ans -= get(w - d - k + 1);
update(d + 1, 1);
}
}
del[c] = 1;
for(auto [v, w] : g[c]) if(!del[v]) calc(v);
}
void solve(){
init();
calc(1);
cout<<ans * 2;
}
signed main(){
ios::sync_with_stdio(false);
cin.tie(NULL);
if(fopen(task".inp", "r")){
freopen(task".inp", "r", stdin);
freopen(task".out", "w", stdout);
}
int nTest = 1;
// cin>>nTest;
while(nTest --) solve();
// cerr << "\nTime: " << 1.0 * clock() / CLOCKS_PER_SEC << "s\n";
return 0;
}
/*
*/
